<div id="app">
    <b-form-group id="mygroup"
                  label="Example Label"
                  description="Enter your fullname."
                  :feedback="text.length?'':'Please enter something'"
                  :state="text.length?'valid':'invalid'">

        <b-form-input v-model="text"></b-form-input>

    </b-form-group>
</div>
